U.S. candidates for the 2016 presidential election have been stroving to outdo each other being tough on Iran in the wake of a landmark nuclear deal.

Amid criticism among Republican candidates, the deal found a supporter in Democratic frontrunner Hillary Clinton. But Clinton stressed on July 14 that she was as ready as her Republican opponents to crack down on any misstep by longtime adversary Iran.

"The message to Iran should be loud and clear: We will never allow you to acquire a nuclear weapon; not just during the term of this agreement -- never," she said. "As president, I would use every tool in our arsenal to compel rigorous Iranian compliance."

When vying for the Democratic nomination in 2008, Clinton took a tough line on Iran, saying she would "obliterate" the country if it used nuclear weapons against Israel.

Later, as President Barack Obama's first secretary of state, Clinton was instrumental in laying the groundwork for the grueling negotiations that led to the deal.

Within the Republican camp, presidential hopefuls signaled they would pounce on her support for the deal as a weakness to exploit during the election.

Most of the large field of Republican candidates have already vowed to repeal the deal as one of their first acts in the Oval Office, if the Republican-led Congress doesn't succeed at overturning it before then.

Like most Republicans, Bush contends that the basic goal of the deal -- preventing Iran from developing nuclear weapons for at least 10 years -- is unacceptable.

Republicans say the United States should have insisted on preventing Iran from attaining any nuclear capabilities at all, despite its longstanding nuclear research program, which Iran insists is peaceful and which would be preserved in part under the deal.

The bargain "will be remembered as one of America's worst diplomatic failures," said Wisconsin Governor Scott Walker.

"We need a president who will terminate that bad deal with Iran on day one," he said. "I will put in place crippling economic sanctions on Iran and I will convince our allies to do the same."

Florida Senator Marco Rubio and former Texas Governor Rick Perry also vowed to rescind the agreement upon taking office.

"It will be left to the next president to return us to a position of American strength and reimpose sanctions on this despicable regime until it is truly willing to abandon its nuclear ambitions and is no longer a threat to international security," Rubio said.

The early posturing over the Iran deal comes as the voting public is registering deep ambivalence about Iran, which has embedded itself in many American minds for repeatedly branding the United States as the "Great Satan."

Only a slim majority of Americans backs diplomacy with Iran, while 56 percent consider Iran an enemy, according to a new Associated Press-GfK poll.

Israel is loudly trumpeting that it sees the agreement as a threat to the country's very existence.

Republican contender Lindsey Graham, a senator from South Carolina, called the deal a "possible death sentence for Israel."

Despite their vows to dismantle the deal, Republican presidential candidates would have a hard time carrying out those threats if they gained control of the White House next year.

"The next president can start from scratch," said Bob Corker, chairman of the Senate Foreign Relations Committee and a leading Republican voice in Congress on Iran.

"What would have happened, though, is the international sanctions process would have been totally dismantled" in the meantime, he said.